Cushioning device



April 19, 1932. .H. J. Kol-:HLY

CUSHIONTNG'DEVICE Filed April 29, 1929 Patented pr. 19, 1932 I UNITED STATES PAIENr OFFICE HARRY IxOEIILY, OF DAYTON', OHIO, AssIGNOR To DELOO PRODUCTS CORPORATION,

. OE DAYTON, OHIO, A CORPORATION OE DELAWARE CUSEIONING DEVICE Application filed Apri 29,

This invention relates to electric motors and in particularto a device for vlauiiing or Vcushioning the end play of the rotor. y

Various methods have been used to. cushion b the endplay of the rotors or armatures. One of the common forms is the use of spring washers intermediate a shoulder on the armature shaft and the frame ofthe motor. This however,A isv objectionable for motors used where silence is required, as for example motors used in household appliances. The

spring washers rotate at various speeds, some at substantially the speed vof the armature, others at various lower speeds. lIn other words, there are aplurality of pairs of 'surfaces in frictional engagement. Whenever one surface slips relative to another sound may be produced. The greater the number of sources of sound, the louder it will be.

The object of this invention-is to suppress the unwelcome sounds from an electric motor by reducing the number of sources of noises. This has been accomplished bymounting on each end of the armature shaft a member having a surface engaging the end frame. of the-motor, said member being fixed to rotate with andxfree to move axially on the shaft, and mounting resilient means engaging said member and said shaft for biasing the shaft in a direction parallel to its axis, the resilient means rotating at the same speed as the shaft. This reduces the number of surfaces having relative rotary movement. Instead of a plun rality of surfaces moving relative to each other, only two surfaces on each end have arelative movement. When the resilient means or washers rotate'with the shaft it has been found that this silences the motor.

Further objects and advantages of the present invention will he apparent from the following description, reference being 'had to the accompanying drawings, wherein a' preferred form ofthe embodiment of the present invention is clearly shown.

In the drawings:

Fig. 1 shows an electric motor with parte broken away so as to show the invention in section.

Figs. 2 and 3 are end and side views of a o spring washer.

rotates with the shaft 20 but is freely movable this invention.

1929.' serial ne 358.7%.

,InAthe drawings the reference .character 10 indicates an electric motor having end frames 12 and 14 provided with bearings -16 and 18, respectively.. The armature shaft20, having the shoulders 22 and 24, is journalled in the 55 bearings 16 and 18. An' annulus or floatingV collar 26, provided with a groove 28 extending parallel tothe axis of the annulus cooperating with a key 30 seated in the shaft 20,

longitudinally or axially along the shaft. Intermediate the annulus 26 and the shoulder 22 on the armature shaft 20 is mounted a plu- By providing the annulus 26 with a smooth finished surface 34 which cooperates with a finished end 36 of the bearing 16 ver little noise, if any, will be produced by t e two surfaces 34 and 36 rotating relative to each other, yespecially when these surfaces are properly lubricated. f

Adjacent the bearing 18 is-mounted an annulus 40 provided with an internal groove 28a extending parallel to the axis'of the annulus said groove receiving a key 42, Vsecured to the shaft 20, whereby the annulus 40 is fixed to rotate with and free to move longitudinally along the shaft. Mounted intermediate the annulus 40 and the shoulder 24Warefaewplurality of washers 44 biasing the shaft 20 to the left as viewed in'Fig. 1, againstthe resilient washers 32 already described. The contacting surface between the bearing 18 and the annulus 40, is also nished so as to rotate smoothly with respect to each other.

In this preferred embodiment 'two an-p; nuluses and two sets of resilient washers have'l been disclosed, the scope of the invention however, is not limited to the useof two am 'nuluses' and twosets of resilient' washers, aSy

two members. and two sets of helical-springs could be used or some other resilient members without departing from the purvlew 'of' rlhis invention has beenvdisclosed in 'combination with the armature shaft of'an elec-s Vao tric motor, Thel scope of the invention is4 not limited to the cushioning of an amature as the device hasa general application to the cushioning and silencing of any rotary member which `has an end play.

While the'form of embodiment of the present invention as herein disclosed, constitutes p a referred form, itis to be understood that otlier forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is` as follows: 1. A device for cushioning axial movement of an armature shaft journalled in the end frames of a motor, comprising. in combina-j tion, a member mounted on said shaft having a surface engaging the frame of the4 motor,

said member being fixed tofrotate with and free to move axially on the shaft; a resilient washer engaging said member and said shaft for biasing the shaft in a direction parallel to its axis.

. 2. A device for limiting axial movement of an armature shaft journalled'in the end frames of a motor, said shaft having a pair of shoulders, one lspaced a short distance from one end frame and the other a short distance from the other end frame, comprising in combination, a member fixed-to rotate with and free to move axially on said shaft, lsaid member having asurface in contact with one of the end frames; resilient means mounted intermediate one of said shoulders and said member biasing the shaft in a direction parallel to the axis of said shaft, said resilient means being gripped by the member and the shoulder so as to rotate at the same speed as the shaft and the member; a second member fixed to rotate with and free to move j interposed between the abutment and the adv lacent end of the collar, said washer biasing axially on` said shaft, said,v second-member having a surface in contact with the other end frame; a second resilient means ,mount- Ied intermediate the second member and the other shoulder biasing the shaft a direction opposite to the, direction the shaft is biased by said first means, said secordresilient means being gripped by the memberand the shoulder so as to rotate at the same speed as theshaft and the second member, thereby reducin chattering noises. I

3.- A evice for cushioning the axial movement of a rotatable shaft comprising, in combination, bearings supporting said shaft; a collar carried upon said'shaft so asto be rotatable with and longitudinally .movable relative to the shaft, one surface of said collar engaging a bearing of the shaft; an abutment on said shaft spaced from the collar thereon; and a resilient washer on the shaft,

the shaft. in a direction arallel to its axis.

` In testlmony whereof hereto aii'x my signature;

' HARRY J. KOEHLY. 

